Iain Duncan Smith has warned rebel Tory MPs that they must unite behind his leadership if the party is to be taken seriously.

The embattled Tory leader, referring to efforts to "undermine" him, told a packed press conference that the Conservatives "cannot go on in this fashion."

Mr. Duncan Smith had spent the morning locked in crisis talks after hastily cancelling a scheduled appearance at a press conference on housing policy.

"I cannot allow the efforts of a dedicated team in parliament or of hundreds of thousands of hard-working volunteers to be sabotaged by self-indulgence or indiscipline."

Eight Tories - including former Conservative leadership challengers Michael Portillo and Ken Clarke - defied a Conservative three line whip (an order to vote a particular way) to back giving unmarried and gay couples the ability to adopt.

BBC political correspondent Nick Assinder answered your questions in a LIVE forum.

"Unite or die" - that was the gauntlet thrown down by Iain Duncan-Smith to the Tory Party today. A rebellion by Conservative Back-Benchers including big names - Michael Portillo and Ken Clarke - over the Adoption Bill led to crisis talks all morning.

Now the leader's turned on his critics. But is his call for unity going to work or is this now the end game for the embattled Tory leader?

Nick a very straightforward question to start with: Ian Baxter, Scotland: Do you think IDS has blundered badly over this?

Nick Assinder:Well frankly Ian I do. I think that at certain stages throughout this crisis - and it is a crisis now I think for Iain Duncan-Smith - he has made some, in my view, tactical errors. Insisting on a Whip on what many people thought should have been a conscience vote, was an error in retrospect. Then saying it was actually a soft Whip and people if they didn't turn up, that was ok by him, made matters worse. And really things have been compounded since then.

When people rebelled, what do you then do? He must have asked himself the question at some point - if somebody defies this three-line Whip, defies my authority - what do I do? We've now got the answer - nothing.

Susanna Reid: Pascal Jacquemain, Welwyn Garden City, UK (French): Wasn't it a huge mistake from the Tories to impose a three line whip on an issue which is one of conscience rather than policy?

What was Iain Duncan-Smith thinking when he put a three line on the Adoption Bill?

Nick Assinder: Indeed. There are two schools of thought here. The first is - and this was a very clever Labour bear trap - they say it'll be a conscience issue, tempting the Tories down that route. The Tories can't do it, particular as Mr Duncan-Smith at the moment is trying to appease the right wing in the party who thinks he's adopting the left-wing, modernisers agenda. So it may well have been that the Tory leader thought by making this subject of a Whip, he was doing something that would actually please the right for once.

Susanna Reid: Rob, Belgium (UK National): Why doesn't everyone think that Iain Duncan-Smith is absolutely spot on? The party must unite or it will die and split into factions like Old Labour and the SDP. Why don't Clarke and Portillo - who both lost leadership contests - realise the majority of Conservatives don't want them?

Nick Assinder:Well indeed. I think a lot of people do think that Iain Duncan-Smith is adopting the right tone certainly and that his "unite or die" message is the right message. And indeed a number of people are asking why don't the likes of Michael Portillo and Kenneth Clarke see this themselves.

I think their answer would probably be that yes, they think the party should unite, but actually around something slightly different and that you need somebody in a position in that job who can, if you like, force unity. That's what I think Iain Duncan-Smith is trying to do at the moment in this stage in the game. He is trying to impose unity and we shall see how that turns out.

Susanna Reid: Eamonn McGuinness, UK: Who advises Iain Duncan-Smith? I can't see him lasting much longer. Although I bet the Labour Party wish Iain Duncan-Smith would stick around until the next election!

Nick Assinder:Well indeed. Interestingly I was literally just moments ago speaking to a Labour Whip who offered to buy me champagne - which I declined. He was saying - oh, we've got him on the run and I said - oh, come on, surely you should be saying, we want to keep him there because of the perceived trouble he is in. Yes, indeed actually, we'd much rather have him there until the next election. They always say that don't they.

But yes, he is in trouble. The Labour Party is going to take their advantage out of this. Tomorrow's Question Time between Iain Duncan-Smith and Tony Blair will be one of the most closely watched, I think, for a long time.

Susanna Reid: John says: I am a Labour voter, but even I am getting concerned now at the lack of a decent opposition. Isn't it true that without strong opposition, the parliamentary democracy cannot function as it should, and this is the situation we find ourselves in now?

Nick Assinder:A very good point and a point that I think is being made from all sides.

Charles Kennedy, the Leader of the Liberal Democrats, regularly makes this point of course - as he may well do and likes to portray his party as the real opposition now - the effective opposition. It is a real problem.

What of course often happens and why the Labour Party and the Labour Party supporters, like our e-mailer, may be worried about of course is that if a government as powerful with such a big majority as the Labour Government doesn't have an effective official opposition, they get it from their own Back-Benchers and that of course does happen and has happened in the past.

And of course, history shows us that Margaret Thatcher for a long time had no effective opposition and she was warned about exactly that by her own side at that time as well.

Susanna Reid: Iain Duncan-Smith was talking about unity today - "unite or die". Chris Taylor, UK says: This is a bit rich coming from Iain Duncan-Smith. Wasn't he a rebel himself in the last Conservative administration?

Nick Assinder:It's one of the big problems he has of course. That each time Iain Duncan-Smith tries to lay down the law and suggest that loyalty is everything, that not towing the leadership line is a sin punishable by death, it immediately raises the question - well, so why did you persist in your plan of "guerrilla warfare" during John Major's time in office? That deeply frustrated John Major, as I'm sure we'll remember and his language was quite colourful on more than one occasion about the people who were frustrating his plans.

It's a major problem for Iain Duncan-Smith and I guess all he can do is put his hands up and face the fact that he will get that sort of criticism. Nonetheless, I still think that he does need to take that line to try and hammer home this unity line because it is the divisions and arguably it was that division that helped "do" for John Major.

Susanna Reid: Emily Tuttiett, Wales: Who do you think will take the party down the road of reform which Iain Duncan-Smith. has begun?

Is Iain Duncan-Smith in a position to continue, considering that three line Whip on the relaxation of the rules over gay couples and unmarried couples adopting children? Is he in a position to continue or does that look like he doesn't want to reform the party?

Nick Assinder:No, I think he genuinely does want to reform the party. I think there's this problem about "talking left and acting right" that some have suggested is one way of him moving forward. I don't think that will succeed.

I think most people in the Tory Party agree that there has to be change. Now there is obviously the argument between the so-called "Mods" and the "Rockers". Iain Duncan-Smith has decided that on certain key policies - like what you might describe as more liberal policies - the party needs to adopt those, be more inclusive, more outward looking.

Susanna Reid: What kind of policies would you consider that would cover?

Nick Assinder:I think that covers a whole range of social policies such as adoption in the specific terms. There've been issues on things like gay marriages and so on in the past as well. Also on racism of course, which he was very tough on, when Ann Winterton, made what many believe was a rather wrong-headed, so-called joke, which had very racist overtones - which would have offended a number of people in her audience - he came down hard on her. So he has shown that he is prepared to follow through, I think.

It's the constant sniping, from both sides, that is making his job increasingly difficult. He's got to stick with it, I guess.

Susanna Reid: Roland Smith, Oxford, UK: Do you believe Michael Portillo is now emerging as a kind of spiritual leader and that it will be one of his "pupils" (Bercow/Lansley?) who eventually go for the leadership?

Nick Assinder:I wouldn't like to give the impression I think a leadership challenge is imminent. I think we're in the position at the moment where frankly almost anything is possible.

The Tories are in serious trouble at the moment - I think we have to accept that. It's quite possible that Iain Duncan-Smith can weather this though, I think. But on the specific point about who there could be to replace him as some point in the future.

Michael Portillo has said that he won't do it so many times now that if he suddenly changes his mind, I find - to coin a phrase - it difficult to foresee any circumstances under which his membership would accept that sudden change of heart. So yes, indeed, maybe he wants to see himself - maybe he's trying to play the part - as king-maker, if you like.

There are candidates there. It has to be said, it's not a big field, I don't think. A lot of the people who may be future leaders perhaps haven't spent enough time yet in post. Others, it has to be said, people like Ken Clarke, are seen as very senior, very experienced - past it.

Susanna Reid: R. Forrester, London: Isn't it time for certain more rebellious members of the Tory party to stop raising their voices from the Back-Benches and to allow Iain Duncan-Smith to pull the party together?

Nick Assinder:I think this is the nub of the whole problem. This is what Iain Duncan-Smith wanted - probably felt he deserved after the leadership election and certainly thought the Tory Party needed was a period of consolidation, a period of reflection - sort out some policies which they came out with - whatever you may think of those policies - they did finally fill the policy vacuum at the Party conference with some concrete, fairly logical policies.

That was starting to happen. He expected and wanted a period to carry that through, a period to unite the party, get over the traumas of two horrific election defeats and gradually move forward and rebuild. And he clearly feels he's just not being given the chance to do that. He's having to fight so many battles on so many different fronts from people who should be on his side, that his attention is constantly being distracted from that job.

Susanna Reid: Stuart says: Isn't what the Tory Party are lacking is a clear position on anything?

Doesn't Iain Duncan-Smith have a terribly difficult balancing act to do between the group which wants to take the Tory Party into the 21st century and the hardcore, old-fashioned Tories? Is it time now for the Tory Party to split into two perhaps?

Nick Assinder:I don't know about splitting into two - we see what happened with the Labour Party and I can see that that may be the thought behind that question. Splitting into two - I don't know, I think that would probably be disastrous for the Tory Party.

It may well be that Iain Duncan-Smith has to be a bit more explicit about which of "Mods" and "Rockers" - for want of a better phrase - which of those routes he wants to take the party down and closes the door on the other group in whatever form he may wish to do that. That may be a way forward.

But as you say, it is a difficult balancing act. If you want to keep the traditionalists on board - and bear in mind a lot of those traditionalists are the people in place in the local authorities, in local constituency associations. You can't just dismiss them, you can't just consign them to the dustbin of history.

Susanna Reid Well especially as so many of them voted for Iain Duncan-Smith presumably. What do you about that group of traditionalist for whom, for instance on this particular issue - the Adoption Bill - gay couples, unmarried couples, adopting children - that sort of issue would be anathema for a huge hardcore of traditionalists . What does Iain Duncan-Smith do about that really solid group of support for him?

Nick Assinder:Indeed. I think on that specific issue, he was wrong to make it a whippable vote, frankly - exactly for the reasons you just stated. It could quite easily and quite legitimately have been put under the category of a conscience vote. It's for each individual to make up their own minds as they do over things like the death penalty, abortion and so on. I think that would have been perfectly fair.

On other issues, there's a job of persuasion perhaps to be done - to persuade people that certain attitudes maybe towards certain groups in society, certain races, cultures and so on, are no longer tolerable and that is job that has to be done. Frankly I don't see a sign of great resistance to that in the vast body of the Tory Party.

The Conference was quite interesting on that. I certainly expected slightly more opposition to that sort of talk from the platform than actually happened. And when you looked at the audience at the Tory Party conference, it was exactly the sort of people we're talking about - traditionalists - what used to be called the "blue rinse brigade". They're still there, they're still very powerful - they make or break leaders now. But they did seem to be open-minded - they did seem to be open to this new agenda.

Susanna Reid: Brian: Do you think the Tories will have to spend a lot more time in the wilderness yet, searching for a genuine leader with some positive ideas?

Nick Assinder:They've got one heck of a fight in front of them. There are Tories at the moment - quite openly on the Back-Benches, and this is part of the problem at the moment - openly worrying about losing their seats.

Susanna Reid: Rob, UK: Do you think IDS has to go and go soon?

Nick Assinder:You're not going to get me betting on that one - that's far too dangerous. I think he can weather this. I don't think there is any doubt he can weather this. I fear he may have to spill some blood if he's going to do that though.

Susanna Reid: Nick, thanks for joining us. This has been a BBC Interactive Forum. Thanks very much for watching. Goodbye.

This forum has ended. Thank you for your questions.

VOTE RESULTS

Can the Tories unite?Yes 16.96% No 83.04% 12733 Votes CastResults are indicative and may not reflect public opinion